Production of dimensionally stable and shape-retaining garments of cellulosic fabrics

ABSTRACT

DIMENSIONALLY STABLE AND SHAPE-RETAINING GARMENTS FROM CELLULOSIC FABRICS ARE PREPARED BY THE STEPS OF IMPREGNATING THE FABRIC WITH TWO DIFFERENT POLY-N-METHYLOL COMPOUNDS, CURING ONE OF THE POLY-METHYLOL COMPOUNDS, MAKING THE GARMENTS, AND THEN CURING THE OTHER POLY-N-METHYLOL COMPOUND.

United States Patent Int. (:1. D06m 13/12, 13/34 US. Cl. 8-116.3 13 Claims ABSTRACT OF THE DISCLOSURE Dimensionally stable and shape-retaining garments from cellulosic fabrics are prepared by the steps of impregnating the fabric with two different poly-N-methylol compounds, curing one of the poly-N-methylol compounds, making the garment, and then curing the other poly-N-methylol compound.

This invention relates to a new process for the manufacture of dimensionally stable and shape-retaining garments from cellulosic fabrics impregnated with two different poly-N-methylol compounds and an acid curing catalyst, one of the said poly-N-methylol compounds being cured before and the other after manufacture of the garment. The invention also relates to the garments obtained by the said process.

It is known that dimensionally stable and shape-retaining garments may be prepared from cellulosic fabrics by impregnating the fabrics with one or more etherified poly-N-methylol compounds and acid curing catalysts in aqueous solution, carefully drying the impregnated fabrics, making them into garments and subjecting the readymade garments to a heat treatment with simultaneous shaping, the poly-N-methylol compounds being condensed or cured under the influence of the catalysts, i.e., they react with themselves or with reactive groups of the fibrous material to form coordinative bonds.

The advantage of the said processes which are usually referred to as deferred-cure, delayed-cure or permanent press techniques, is that not only are the fabrics used for making the garments made resistant to creases and dimentional changes as in the case of conventional processess, but the seams and desired creases in the garments are also stabilized.

The processes of the said kind also have considerable disadvantages. For example, expensive curing ovens are required for the condensation of the poly-N-methylol compounds. The garments must also be made larger than actually required because the fabrics shrink during shaping while condensation has not been completed. Moreover, the conventional processes call for very drastic curing conditions which only few dyes stand up to without damage or change of shade. Processing of dyed material by the said processes therefore frequently involves considerable difliculty. According to the prior literature on the processes in question it is essential that partial reaction of the poly-N-methylol compounds prior to garment manufacture and shaping be avoided. The term poly-N- methylol compounds as used herein means monomeric substances containing two or more, preferably two to four, hydroxymethyl or low molecular weight alkoxymethyl groups attached to nitrogen. They are usually derived from ureas, thioureas, 1,3,5-triazines, annular compounds having at least one urea structure, acid amides, monourethanes or diurethanes (=monoand dicarbamates).

Patented Feb. 16, 1971 It is an object of the present invention to provide a process for the manufacture of dimensionally stable and shape-retaining garments which can be easily carried out by garment manufacturers without the need for expensive curing equipment. Another object of the invention is to enable textile material intended for use in the manufacture of dimensionally stable and shape-retaining garments to be cut immediately to the size required for the garments, thus avoiding deviations from the usual garment sizes. A further object of the invention is to provide a process for the manufacture of dimensionally stable and shape-retaining garments which attacks the dyes on the fabrics to a lesser extent, thus enabling a wider range of dyes to be employed. These and other objects are achieved by the present invention.

We have found that partial reaction of the poly-N methylol compounds prior to garment manufacture and Shaping does give particularly good results if it is carried out under controlled conditions, and that the above-mentioned disadvantages can be avoided by impregnating cellulosic fabric with at least two poly-N-methylol compounds whose condensation characteristics differ markedly, namely (a) at least one poly-N-methylol compound which condenses at a low temperature and may be etheritied and (b) at least one poly-N-methyl0l compound which condenses at a high temperature and may be etherified and, additionally, with (c) at least one acid curing catalyst, drying the impregnated fabric under mild conditions, heating it to a moderate temperature so as to condense only component (a), making it into garments and then heating the garments with simultaneous shaping to a higher temperature in order to condense component (b).

In line with this general inventive concept the process according to this invention comprises impregnating fabrics with (a) one or more poly-N-methylol compounds of the formula where the substituents R which may be identical or different, are hydrogen atoms or alkyl groups having 1 to 4 carbon atoms, R is -CHCH-, oH2oH -cH l or O R OR OR:

Rv iv OR the substituents R which may be identical or different, are hydrogen atoms, alkyl groups having from 1 to 4 carbon atoms or groups of the formula R OCH R is an alkylene group having from 2 to 4 carbon atoms, R is methyl or ethyl and n is zero or 1, the compounds containing at least two R OCH groups, and

(c) one or more acid curing catalysts, drying them at a fabric temperature of up to 100 C., treating them at a temperature of 110 to 125 C. to condense component (a), making them into garments and treating the garments at a temperature of at least 140 C. with simultaneous shaping to condense component (b).

Compounds of group (a) are N,N-dimethylol compounds of urea, N,N'-ethyleneurea (=imidazolidone-2), N,N'-trimethyleneurea (=N,N-propyleneurea or hexahydropyrimidone-Z), hydroxyhexahydropyrimidone-2, urone (=5-oxahexahydropyrimidone-2) as well as their derivatives partly or completely etherified on the methylol groups and/or nuclear hydroxyl groups with methanol, ethanol, propanols or butanols.

Compounds of group (b) are for example the N,N'- dimethylol compounds of glyoxal monoureine 4,5-dihydroxyimidazolidone 2), 4 hydroxyhexahydropyrimidone 2, 4-hydroxy-5,5-dimethylhexahydropyrimidone-2 and ethylene glycol-bis-N-ethylcarbamate, the N,N-dimethylol compounds of ethyl, propyl and butyl carbamate, the di-, triand tetramethylol compounds of the dicarbamic acid esters of ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol as well as their derivatives partly or completely etherified on the methylol groups and/or nuclear hydroxyl groups with methanol, ethanol, propanols or butanols.

Acid curing catalysts are compounds that form acids under the conditions of condensation. They are widely used to accelerate the condensation of N-methylol compounds. Examples are aluminum sulfate, zinc chloride, zinc nitrate, ammonium chloride, ammonium nitrate, ammonium phosphates and salts of strong acids, especially hydrochloric acid, and amines, especially hydroxyalkylamines, such as ethanolamine, diethanolamine, Z-hydroxy- 2-methylpropylamine and preferably magnesium chloride and magnesium sulfate. The catalysts may be used alone or in admixture with each other.

By varying the amounts and relative proportions of compounds (a) and (b) the process according to this invention may be adapted to suit the type of fabric used and the garments to be manufactured. It has been found advantageous to impregnate the fabric with a total of 3 to 12%, preferably 4 to 8%, based on the dry weight of the fibrous material, of poly-N-methylol compounds or ethers thereof, and to apply the compounds of groups (a) and (b) in the weight ratio of 1:3 to 3:1, preferably 2:3 to 3:2. The acid curing catalysts are applied in the usual amounts, i.e., preferably in amounts of 4 to 30% based on the total weight of the poly-N-methylol compounds or ethers thereof.

The compounds (21), (b) and (c) may be applied to the fabric separately. It is however simpler and therefore preferred to dissolve them in a. common, preferably aqueous, bath and to impregnate the fabric therewith. In many cases it is advantageous to also add to the impregnating bath wetting agents and/or conventional agents for the treatment of fibrous materials, e.g., optlcal brighteners, water-repelling agents, softeners and finishes. Wetting agents are for example salts of alkylnaphthalenesulfonic acids, alkali metal salts of sulfonated dioctyl succinate andadducts of alkylene oxides to fatty alcohols, alkylphenols, fatty amines and the like. Water-repelling agents are for example the well-known paraflin wax emulsions containing aluminum or zirconium, and also siliconcontaining formulations and perfiuorinated aliphatic compounds. Suitable softeners are for example ethenoxylation products of high molecular weight fatty acids, fatty alcohols and fatty amides, high molecular weight polyglycol ethers and esters thereof, high molecular weight fatty acids, fatty alcohol sulfonates, stearyl-N,N-ethylene urea and stearylamidomethylpyridinium chloride. Examples of suitable finishes are cellulose ethers or esters and alginates and particularly solutions or dispersions of synthetic polymers, e.g., polyarnides, ethenoxylated polyamides, polyvinyl ethers, polyvinyl alcohols, polyacrylic acid or esters or amides thereof and also of corresponding methacrylic compounds, polyvinyl propionate, polyvinylpyrrolidone, copolymers, e.g., of vinyl chloride and acrylic esters, butadiene and styrene or acrylonitrile, a-dichloroethylene, B-chloroalkylacrylic esters or vinyl-fi-chloroethyl ether and acrylamide or amides of crotonic or maleic acid, or N-methylolmethacrylamide and other polymerizable compounds, preferably polyethylene. The solutions or dispersions of synthetic polymers are advantageously used in amounts of 5 to 30% calculated as solids and related to the weight of compounds (a) and (b).

It is particularly advantageous to add to the impregnating bath aqueous dispersions of copolymers of 1 to 25%, preferably 1 to 5%, of an N-methlolamide of acrylic acid and 99 to preferably 99 to of one or more other polymerizable compounds, such as particularly esters of acrylic acid and monohydric or dihydric alcohols having up to four carbon atoms, acrylamide and mixtures thereof. Particularly good results have been obtained by using the said copolymers in amounts of 5 to 30% calculated as solids and related to the weight of compounds (21) and (b). Greater dry crease recovery angles and improved durability of the finish may thus be obtained without any loss of strength.

The material is preferably impregnated with the liquor in the usual manner, preferably by padding, and the impregnated material is squeezed in conventional manner to remove excess impregnating liquid. In general, the wet pickup is between 50 and 100% by weight.

Drying of the impregnated fabric is carried out in conventional manner. Particularly good results are obtained by drying the fabric to a residual moisture content of 4 to 8%. The heat treatment by which components (a) are to be condensed is carried out by methods usual in resin finishing, care being taken to ensure that the temperature does not rise to a point at which components (b) also start reacting. An upper temperature limit of C. provides an adequate safety margin. In general, condensation of the components (a) has proceeded sufficiently after 2 to 5 minutes that success of the reaction is ensured. Prior to or during the heat treatment the fabric may be mechanically shaped, for example by calendering, chintzing, schreinerizing, embossing or pleating. The shape thus imparted is fixed by condensation of components (a).

The fabric thus treated which still contains the compounds of group (b) in substantially unchanged condition is then cut and made into garments, either immediately or after a storage period of up to 18 months, for example several months or a year later.

The ready-made garments are then subjected, with simultaneous shaping, to a second heat treatment at a temperature at which compounds (b) are condensed. The lower temperature limit for this treatment is approximately C., while the upper limit depends on the temperature resistance of the fabric. It may be for example 180 or 200 C. It is preferred to carry out the heat treatment at to C. Condensation is usually completed after 30 to 120 seconds. Good results are obtained by using steam presses, particularly those with additional electric heating and using pressures of the order of 2, kg./cm. An advantageous procedure is to carry out the shaping and thermal treatments in three steps without there being any need to remove the goods from the press during the process: 1. Steaming in the press until the garment has picked up approximately 20% of moisture, 2. Drying, if desired under vacuum. 3. Condensation of compounds (b) in the press. The above procedure is to be preferred if the thread used for serving the garment has not been resin-finished. If resin-finished thread has been used, condensation may be carried out without previous steaming in the press. If a high-temperature press is not available,

the garment may be shaped with an iron or press of a lower heat capacity and condensation of the substances (b) may be carried out in a heat chamber.

The garments thus treated may be washed to remove the catalyst, although in many cases washing may be dispensed with. They are completely stable dimensionally, retain their shape during laundering and their appearance is unaffected by numerous machine washes.

As compared with the prior art processes discussed above the process according to this invention has the advantage that it can be carried out without any expensive curing equipment, that the garment corresponds in size exactly to the size to which the material has been cut and that it provides a much surer way to produce dimensionally stable and shape-retaining garments having smooth seams that are not deformed by laundering. It could not be foreseen that this beneficial elfect would be achieved in the said manner, as it was to be expected that the presence of poly-N-methylol compounds condensing under mild conditions would result in cocondensates of all re active components present being formed in the first stage of condensation so that another condensation could not be carried out satisfactorily, particularly as prior condensation was found to be detrimental in the conventional processes. A further advantage of the process according to this invention is that it attacks dyes less than the prior art processes and can therefore be used for a much larger number of dyed fabrics. The process may be used on fabrics consisting of or containing natural or regenerated cellulose, e.g., cotton, linen, viscose staple, viscose rayon and cuprammonium rayon in addition to other types of fibers, e.g., of wool, cellulose esters and particularly of synthetic materials, such as polyamides, polyesters, polyolefins and acrylonitrile polymers.

The invention is further illustrated by, but not limited to, the following examples in which the parts and percentages specified are by weight.

EXAMPLE 1 Cotton poplin fabric weighing 220 g. per sq. m. is padded with a liquor having the following composition:

75 parts of a 50% aqueous solution of N,N-dimethylolethyleneurea (=N,N'-dimethylolin1idaz0lidone-2 75 parts of a 50% aqueous solution of N,N'-dimethylolglyoxal monoureine,

30 parts of a 40% aqueous dispersion of a copolymer of 89 parts of butyl acrylate, 5 parts of butanediol diacrylate, 3 parts of N-methylolrnethacrylamide, and 3 parts of acrylamide,

1 part of the adduct of 7 moles of ethylene oxide to 1 mole of isooctylphenol,

20 parts of a 30% aqueous primary polyethylene dispersion, and

20 parts of crystalline magnesium chloride,

made up to 1000 parts with water.

The wet pickup is 75%. The fabric is dried to a residual moisture content of 7% at an air temperature of 110 C., the temperature of the fabric remaining below 100 C., and then exposed to a temperature of 125 C. for 3 /2 minutes. After a simple machine wash at 60 C. the fabric shows a shrinkage of 1% (both warp and weft), whereas untreated fabric shrinks 11% in the warp and 7.5% in the weft.

The fabric thus treated is kept for 15 months without washing and then made into a pair of trousers.

The readymade garment is subjected to a three-step pressing process using a steam press having an additional electric heating. The entire process is carried out at 170 C. In the first (steaming) step the fabric absonbs up to of moisture. It lasts about 20 seconds. In the second, which lasts about 10 seconds, the excess moisture is removed, and in the third the condensation of the sensitized chemicals is completed in approximately 90 seconds.

The trousers thus processed were Worn for seven twoday periods and after each period machine washed at C. In the first (steaming) step the fabric absorbs up to 20% of moisture. It lasts about 20 seconds. In the second, drip dry. After the seventh wash the trousers showed no change in shape, size or smoothness.

EXAMPLE 2 A poplin fabric consisting of a blend of polyethylene terephthalate and cotton at a weight ratio of 65:35 (warp and weft) and weighing 125 g. per sq. m. is impregnated with a liquor having the following composition:

65 parts of a 50% aqueous solution of N,N-dimethylolethyleneurea,

65 parts of a 50% aqueous solution of N,N-dimethylolethylurethane ethyl-N, N-dimethylol carbamate), and

18 parts of crystalline magnesium chloride,

made up to 1,000 parts with water.

The wet pickup is 60%. The fabric is dried at C. to a residual moisture content of 6% and then exposed to a temperature of 125 C. for three minutes. After a machine wash at 60 C. it shows a shrinkage of 1.2% (warp and weft), whereas untreated fabric shrinks 10% in the warp and 6.5% in the weft. The fabric thus treated is kept for 12 months without washing and then made into a shirt. Ironing is carried out as described in Example 1. The resultant shirt has excellent crease resistance and is dimensionally stable and shape-retaining.

EXAMPLE 3 Cambric consisting of a blend of polyethylene terephthalate and cotton at a weight ratio 50:50 (warp and weft) and weighing 100 g. per sq. m. is impregnated with a liquor having the following composition:

50 parts of a 50% aqueous solution of N,N'-dimethylolpropyleneurea (:N,N' dimethylolhexahydropyrimidone-2,

50 parts of a 50% aqueous solution of N,N-dimethylol- 4-methoxy-5,S-dimethylpropyleneurea (:N,N-dimeth ylol-4-methoxy-5 ,5 -dimethylhexahydropyrimidone-2 25 parts of a 30% aqueous primary polyethylene dispersion, and

14 parts of crystalline magnesium sulfate,

made up to 1,000 parts by volume with water.

The wet pickup is 70%. The fabric is dried at C. to a residual moisture content of 7% and then exposed to a temperature of C. for three minutes. After a machine wash at 60 C. it exhibits a shrinkage of 0.7% (warp and weft), whereas untreated fabric shrinks 8.5% in the warp and 5.5% in the weft. The fabric thus treated is kept for six months without washing and then made into a blouse using sewing thread of polyethylene terephthalate. The readymade blouse is ironed for 15 seconds at C. using the press described in Example 1.

The resultant blouse is crease-resistant, self-smoothing, dimensionally stable and shape-retaining even after several machine washes at 60 C.

EXAMPLE 4 A dyed union fabric consisting of rayon staple and polyglycol terephthalate fibers (50:50) and weighing g. per sq. m. is padded with a liquor which in 1,000 parts by volume contains the following components:

40 parts of N,N'-dimethylolethyleneurea,

40 parts of N,N'-dimethylolurea,

32 parts of N,N'-dimethylolglyoxal monoureine,

30 parts of a 30% aqueous polyethylene dispersion,

2 parts of an adduct of 7 moles of ethylene oxide to 1 mole of isooctylphenol and 30 parts of magnesium chloride,

the rest being water.

The fabric is dried at 100 C. to a residual moisture content of 6% and then heated at 120 C. for 2 /2 minutes to condense the N,N-dimethylolurea and the N,N'-dimethylolethyleneurea.

The fabric is made into a pair of trousers which are treated on a steam press for 30 seconds at 185 C. to condense the N,N'-dimethylolglyoxal monoureine.

The trousers thus processed are unchanged in appearance after several washes.

EXAMPLE Dyed fabric of cotton and polyglycol terephthalate fibers (67:33) weighing 200 g. per sq. m. is padded with a liquor which in 1,000 parts by volume contains the following components:

37.5 parts of N ,N -dimethylol-N -isobutylhexahydro- 1,3,5-triazinone-2,

30 parts of N,N'-dimethylolglyoxalmonoureine,

40 parts of a 30% aqueous polyethylene dispersion,

2 parts of an adduct of 7 moles of ethylene oxide to 1 mole of isooctylphenol and 25 parts of magnesium chloride,

the rest being water.

The fabric is dried at 100 C. to a residual moisture content of 6% and heated at 120 C. for 2 /2 minutes to condense the triazinone derivative.

The fabric is then used to make a pair of trousers which are pressed at 185 C. for seconds using a steam press and then aftertreated in a heat chamber for six minutes at 185 C.

The trousers thus processed are unchanged in appearance after several washes.

We claim:

1. A process for the manufacture of dimensionally stable and shape-retaining garments wherein cellulosic fabrics are impregnated with poly-N-methylol compounds or ethers thereof and acid catalysts and then made into garments and the poly-N-methylol compounds are then reacted by heating the garments with simultaneous shaping, which comprises impregnating the fabrics with (a) one or more compounds of the formula L.. -Rl

where R denotes one of the groups -CHz-CHg-, -CHz-CH2CH2, -CH2CIICHgand the substituents R which may be identical or different, denote hydrogen atoms or alkyl groups having 1 to 4 carbon atoms,

where the substituents R which may be identical or different, are hydrogen atoms or alkyl groups having 1 to 4 carbon atoms,

the substituents R which may be identical or different, are hydrogen atoms, alkyl groups having from 1 to 4 carbon atoms or groups of the formula R O-CH R is an alkylene group having from 2 to 4 carbon atoms, R is methyl or ethyl and n is zero or 1, the compounds containing at least two R OCH groups, and

(c) one or more acid curing catalysts in the proportions of 3 to 12% by weight of the compounds of groups (a) and (b) with reference to the dry weight of the fibrous material and 4 to 30% by weight of said catalyst with reference to the total weight of the compounds of groups (a) and (b) and at a Weight ratio of the compounds of group (a) to the compounds of group (b) of 1:3 to

3:1, drying said fabrics at a fabric temperature of up to C. to a residual moisture content of 48%, heating said fabrics to a temperature of to C. to condense component (a), making the resultant fabrics into garments and heating said garments at a temperature of at least C. with simultaneous shaping to condense component (b).

2. A process as claimed in claim 1 wherein the condensation of component (b) is carried out at a temperature of to C.

3. A process as claimed in claim 1 wherein component (a) is N,N-dimethylolimidazolidone-2.

4. A process as claimed in claim 1 wherein component (a) is N,N'-dimethylolhexahydropyrimidone-2.

5. A process as claimed in claim 1 wherein component (b) is N,N'-dimethylol-4,5-dihydroxyimidazolidone-Z.

6. A process as claimed in claim 1 wherein component (b) is N,N-dimethylolethylurethane.

7. A process as claimed in claim 1 wherein component (b) is N,N-dirnethylol-4-methoxy-5,5-dimethylhexahydropyrimidone-2.

8. A process as claimed in claim 1 wherein component (c) is magnesium chloride or magnesium sulfate.

9. A process as claimed in claim 1 wherein the fabric is impregnated with an aqueous polyethylene dispersion in addition to components (a), (b) and (c).

10. A process as claimed in claim 1 wherein the fabric is impregnated, in addition to components (a), (b) and (c), with an aqueous dispersion of a copolymer of 1 to 25% by weight of an N-methylolamide of acrylic acid and 99 to 75% by weight of an acrylic ester of a monohydric alcohol having from one to four carbon atoms, an acrylic ester of a dihydric alcohol having from one to four carbon atoms and acrylamide.

11. A process as claimed in claim 1 wherein components (a) and (b) are applied to the fabric at a weight ratio of 1:3 to 3:1.

12. A process as claimed in claim 1 wherein the condensation of compounds of group (b) is carried out in a steam press by steaming said garments up to a wet pickup of approximately 20%, drying said garments and then condensing said compounds.

13. Dimensionally stable and shape-retaining garments of cellulosic fabrics when made by the process claimed in claim 1.

References Cited UNITED STATES PATENTS 3,304,312 2/1967 Beachem 8116.3X

3,472,606 10/1969 Getchell et al. 8116.3X

FOREIGN PATENTS 1,374,705 8/ 1964 France 8116.2

OTHER REFERENCES Pensa, I. E.; Tesoro, G. C.; Ran, R. 0.; and Egrie, P. H.: Two-stage Curing in the Cross-linking of Cellulosic Fabrics, Textile Research Journal; 1966, vol. 36, N0. 3, pp. 279-288.

Kullman, Russell M. H., et al.: Wash-Wear Finishing of Cotton Fabrics Using Deferred Curing, American Dyestuif Reporter; May 14, 1962; pp. 365-372, 47-54.

J. D. Reid & R. M. Reinhardt: Advances In Textile Processing, vol. 1, 1961, pp. 64-65.

GEORGE F. LESMES, Primary Examiner J. R. MILLER, Assistant Examiner US. Cl. X.R. 2243; 38-144 mg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,5 3, 9 Dated February 16, 1971 Inventor(s) Heinz Bille et a1 It; is certified that error appears in the aboveidentified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line +8, mentiona1" should read mensional Column 4, line 18, "N-methlolamide" should read N-methylolamide Column 6, lines 1 and 2, "C. In the first (steaming) step fabric absorbs up to 20% of moisture. It lasts about 20 seconds. In the second," should read 60 C. using a household detergent and then hung up to Signed and sealed this 29th day of June 1971.

(SEAL) Attest:

ED'\ -IARD M.FLETCHER,JR. WILLIAM E. SCHUYLER, JR Attesting Officer Commissioner of Patents 

